It is presented a method for producing a cured polymer structure from a polymer compound which is UV curable and partly UV transparent. The method comprises injecting the polymer compound into a mold (2), which mold (2) has at least one wall (7) defining a mold space (6) for receiving the polymer compound in the mold space (6). The at least one wall (7) of the mold (2) is UV transparent and comprises a thermoplastic polymer. The polymer compound is then irradiated through the at least one wall (7), by means of at least one UV semiconductor light source, thereby curing the polymer compound to form the cured polymer structure. An assembly for producing a polymer structure and a mold (2) is also presented herein.